The great Epicurus:

Yet much worse still is the man who says it is good not to be born, but “once born make haste to pass the gates of Death.” [Theognis, 427]  For if he says this from conviction why does he not pass away out of
life? For it is open to him to do so, if he had firmly made up his mind
to this. But if he speaks in jest, his words are idle among men who
cannot receive them.

The great Robin Hanson:

I mean, really, the whole human race should go extinct to avoid the risk
that some future kid might suffer at some point?! And since the same
argument applies to non-humans, all life should go extinct?! How could
that ever be a remotely acceptable mainstream position? Cryonics is
silly, and that is not?!